Abstract

Because the deposited 222Rn progeny distribution in lung airways, these sources can contribute hardly to critical cells absorbed dose in neighbourhood of alpha track by the alpha particles from 218Po and 214Po. According to epidemiological data [1], lung cancers are primarily bronchogenic and mainly originate in the first five airway generations of the bronchial tree. Generally for deposited energy calculations, uniform deposit in source layers and the whole layers as sources has been considerated too. Discretional point deposits in the diferent and most important bronqui (BB) and bronchial (bb) layers for main generations is a more realistic case. Because that facts we have calculated the average deposited energy by Monte Carlo in the most important different target cell layers for the main BB and bb branch generations considering the radioactive 222Rn progeny puntual deposit in the source epithelium walls, from this location, It irradiate the neighbor cells in all directions.